I'm having same problem. Have followed publicize set up steps over and over, carefully disconnecting from facebook & removing WP app before starting over. Each time, everything looks good, but posts do not appear.

I can use the Facebook share button in WP to manually post, but would like to automate.

The part about "flushing FB cache" is greek to me, as is the link given to help me flush successfully. Is that my problem?

As you are having trouble with the other methods this one may suit you better. RSS Grafitti http://www.facebook.com/RSS.Graffiti can be used for posting to Facebook walls if you prefer. RSS Graffiti periodically checks the RSS/Atom feeds that you specify and posts any new entries it finds to the Facebook Walls that you specify. You can get any feed written on any wall (Facebook Profiles, Fan Pages, Groups, Events and Application Profile Pages). In fact, multiple feeds to multiple walls. You choose the combination.